xref: /openbmc/linux/fs/xfs/xfs_extfree_item.c (revision 22fd411a)
1 /*
2  * Copyright (c) 2000-2001,2005 Silicon Graphics, Inc.
3  * All Rights Reserved.
4  *
5  * This program is free software; you can redistribute it and/or
6  * modify it under the terms of the GNU General Public License as
7  * published by the Free Software Foundation.
8  *
9  * This program is distributed in the hope that it would be useful,
10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
12  * GNU General Public License for more details.
13  *
14  * You should have received a copy of the GNU General Public License
15  * along with this program; if not, write the Free Software Foundation,
16  * Inc.,  51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
17  */
18 #include "xfs.h"
19 #include "xfs_fs.h"
20 #include "xfs_types.h"
21 #include "xfs_log.h"
22 #include "xfs_inum.h"
23 #include "xfs_trans.h"
24 #include "xfs_buf_item.h"
25 #include "xfs_sb.h"
26 #include "xfs_ag.h"
27 #include "xfs_mount.h"
28 #include "xfs_trans_priv.h"
29 #include "xfs_extfree_item.h"
30 
31 
32 kmem_zone_t	*xfs_efi_zone;
33 kmem_zone_t	*xfs_efd_zone;
34 
35 static inline struct xfs_efi_log_item *EFI_ITEM(struct xfs_log_item *lip)
36 {
37 	return container_of(lip, struct xfs_efi_log_item, efi_item);
38 }
39 
40 void
41 xfs_efi_item_free(
42 	struct xfs_efi_log_item	*efip)
43 {
44 	if (efip->efi_format.efi_nextents > XFS_EFI_MAX_FAST_EXTENTS)
45 		kmem_free(efip);
46 	else
47 		kmem_zone_free(xfs_efi_zone, efip);
48 }
49 
50 /*
51  * Freeing the efi requires that we remove it from the AIL if it has already
52  * been placed there. However, the EFI may not yet have been placed in the AIL
53  * when called by xfs_efi_release() from EFD processing due to the ordering of
54  * committed vs unpin operations in bulk insert operations. Hence the
55  * test_and_clear_bit(XFS_EFI_COMMITTED) to ensure only the last caller frees
56  * the EFI.
57  */
58 STATIC void
59 __xfs_efi_release(
60 	struct xfs_efi_log_item	*efip)
61 {
62 	struct xfs_ail		*ailp = efip->efi_item.li_ailp;
63 
64 	if (!test_and_clear_bit(XFS_EFI_COMMITTED, &efip->efi_flags)) {
65 		spin_lock(&ailp->xa_lock);
66 		/* xfs_trans_ail_delete() drops the AIL lock. */
67 		xfs_trans_ail_delete(ailp, &efip->efi_item);
68 		xfs_efi_item_free(efip);
69 	}
70 }
71 
72 /*
73  * This returns the number of iovecs needed to log the given efi item.
74  * We only need 1 iovec for an efi item.  It just logs the efi_log_format
75  * structure.
76  */
77 STATIC uint
78 xfs_efi_item_size(
79 	struct xfs_log_item	*lip)
80 {
81 	return 1;
82 }
83 
84 /*
85  * This is called to fill in the vector of log iovecs for the
86  * given efi log item. We use only 1 iovec, and we point that
87  * at the efi_log_format structure embedded in the efi item.
88  * It is at this point that we assert that all of the extent
89  * slots in the efi item have been filled.
90  */
91 STATIC void
92 xfs_efi_item_format(
93 	struct xfs_log_item	*lip,
94 	struct xfs_log_iovec	*log_vector)
95 {
96 	struct xfs_efi_log_item	*efip = EFI_ITEM(lip);
97 	uint			size;
98 
99 	ASSERT(atomic_read(&efip->efi_next_extent) ==
100 				efip->efi_format.efi_nextents);
101 
102 	efip->efi_format.efi_type = XFS_LI_EFI;
103 
104 	size = sizeof(xfs_efi_log_format_t);
105 	size += (efip->efi_format.efi_nextents - 1) * sizeof(xfs_extent_t);
106 	efip->efi_format.efi_size = 1;
107 
108 	log_vector->i_addr = &efip->efi_format;
109 	log_vector->i_len = size;
110 	log_vector->i_type = XLOG_REG_TYPE_EFI_FORMAT;
111 	ASSERT(size >= sizeof(xfs_efi_log_format_t));
112 }
113 
114 
115 /*
116  * Pinning has no meaning for an efi item, so just return.
117  */
118 STATIC void
119 xfs_efi_item_pin(
120 	struct xfs_log_item	*lip)
121 {
122 }
123 
124 /*
125  * While EFIs cannot really be pinned, the unpin operation is the last place at
126  * which the EFI is manipulated during a transaction.  If we are being asked to
127  * remove the EFI it's because the transaction has been cancelled and by
128  * definition that means the EFI cannot be in the AIL so remove it from the
129  * transaction and free it.  Otherwise coordinate with xfs_efi_release() (via
130  * XFS_EFI_COMMITTED) to determine who gets to free the EFI.
131  */
132 STATIC void
133 xfs_efi_item_unpin(
134 	struct xfs_log_item	*lip,
135 	int			remove)
136 {
137 	struct xfs_efi_log_item	*efip = EFI_ITEM(lip);
138 
139 	if (remove) {
140 		ASSERT(!(lip->li_flags & XFS_LI_IN_AIL));
141 		xfs_trans_del_item(lip);
142 		xfs_efi_item_free(efip);
143 		return;
144 	}
145 	__xfs_efi_release(efip);
146 }
147 
148 /*
149  * Efi items have no locking or pushing.  However, since EFIs are
150  * pulled from the AIL when their corresponding EFDs are committed
151  * to disk, their situation is very similar to being pinned.  Return
152  * XFS_ITEM_PINNED so that the caller will eventually flush the log.
153  * This should help in getting the EFI out of the AIL.
154  */
155 STATIC uint
156 xfs_efi_item_trylock(
157 	struct xfs_log_item	*lip)
158 {
159 	return XFS_ITEM_PINNED;
160 }
161 
162 /*
163  * Efi items have no locking, so just return.
164  */
165 STATIC void
166 xfs_efi_item_unlock(
167 	struct xfs_log_item	*lip)
168 {
169 	if (lip->li_flags & XFS_LI_ABORTED)
170 		xfs_efi_item_free(EFI_ITEM(lip));
171 }
172 
173 /*
174  * The EFI is logged only once and cannot be moved in the log, so simply return
175  * the lsn at which it's been logged.  For bulk transaction committed
176  * processing, the EFI may be processed but not yet unpinned prior to the EFD
177  * being processed. Set the XFS_EFI_COMMITTED flag so this case can be detected
178  * when processing the EFD.
179  */
180 STATIC xfs_lsn_t
181 xfs_efi_item_committed(
182 	struct xfs_log_item	*lip,
183 	xfs_lsn_t		lsn)
184 {
185 	struct xfs_efi_log_item	*efip = EFI_ITEM(lip);
186 
187 	set_bit(XFS_EFI_COMMITTED, &efip->efi_flags);
188 	return lsn;
189 }
190 
191 /*
192  * There isn't much you can do to push on an efi item.  It is simply
193  * stuck waiting for all of its corresponding efd items to be
194  * committed to disk.
195  */
196 STATIC void
197 xfs_efi_item_push(
198 	struct xfs_log_item	*lip)
199 {
200 }
201 
202 /*
203  * The EFI dependency tracking op doesn't do squat.  It can't because
204  * it doesn't know where the free extent is coming from.  The dependency
205  * tracking has to be handled by the "enclosing" metadata object.  For
206  * example, for inodes, the inode is locked throughout the extent freeing
207  * so the dependency should be recorded there.
208  */
209 STATIC void
210 xfs_efi_item_committing(
211 	struct xfs_log_item	*lip,
212 	xfs_lsn_t		lsn)
213 {
214 }
215 
216 /*
217  * This is the ops vector shared by all efi log items.
218  */
219 static struct xfs_item_ops xfs_efi_item_ops = {
220 	.iop_size	= xfs_efi_item_size,
221 	.iop_format	= xfs_efi_item_format,
222 	.iop_pin	= xfs_efi_item_pin,
223 	.iop_unpin	= xfs_efi_item_unpin,
224 	.iop_trylock	= xfs_efi_item_trylock,
225 	.iop_unlock	= xfs_efi_item_unlock,
226 	.iop_committed	= xfs_efi_item_committed,
227 	.iop_push	= xfs_efi_item_push,
228 	.iop_committing = xfs_efi_item_committing
229 };
230 
231 
232 /*
233  * Allocate and initialize an efi item with the given number of extents.
234  */
235 struct xfs_efi_log_item *
236 xfs_efi_init(
237 	struct xfs_mount	*mp,
238 	uint			nextents)
239 
240 {
241 	struct xfs_efi_log_item	*efip;
242 	uint			size;
243 
244 	ASSERT(nextents > 0);
245 	if (nextents > XFS_EFI_MAX_FAST_EXTENTS) {
246 		size = (uint)(sizeof(xfs_efi_log_item_t) +
247 			((nextents - 1) * sizeof(xfs_extent_t)));
248 		efip = kmem_zalloc(size, KM_SLEEP);
249 	} else {
250 		efip = kmem_zone_zalloc(xfs_efi_zone, KM_SLEEP);
251 	}
252 
253 	xfs_log_item_init(mp, &efip->efi_item, XFS_LI_EFI, &xfs_efi_item_ops);
254 	efip->efi_format.efi_nextents = nextents;
255 	efip->efi_format.efi_id = (__psint_t)(void*)efip;
256 	atomic_set(&efip->efi_next_extent, 0);
257 
258 	return efip;
259 }
260 
261 /*
262  * Copy an EFI format buffer from the given buf, and into the destination
263  * EFI format structure.
264  * The given buffer can be in 32 bit or 64 bit form (which has different padding),
265  * one of which will be the native format for this kernel.
266  * It will handle the conversion of formats if necessary.
267  */
268 int
269 xfs_efi_copy_format(xfs_log_iovec_t *buf, xfs_efi_log_format_t *dst_efi_fmt)
270 {
271 	xfs_efi_log_format_t *src_efi_fmt = buf->i_addr;
272 	uint i;
273 	uint len = sizeof(xfs_efi_log_format_t) +
274 		(src_efi_fmt->efi_nextents - 1) * sizeof(xfs_extent_t);
275 	uint len32 = sizeof(xfs_efi_log_format_32_t) +
276 		(src_efi_fmt->efi_nextents - 1) * sizeof(xfs_extent_32_t);
277 	uint len64 = sizeof(xfs_efi_log_format_64_t) +
278 		(src_efi_fmt->efi_nextents - 1) * sizeof(xfs_extent_64_t);
279 
280 	if (buf->i_len == len) {
281 		memcpy((char *)dst_efi_fmt, (char*)src_efi_fmt, len);
282 		return 0;
283 	} else if (buf->i_len == len32) {
284 		xfs_efi_log_format_32_t *src_efi_fmt_32 = buf->i_addr;
285 
286 		dst_efi_fmt->efi_type     = src_efi_fmt_32->efi_type;
287 		dst_efi_fmt->efi_size     = src_efi_fmt_32->efi_size;
288 		dst_efi_fmt->efi_nextents = src_efi_fmt_32->efi_nextents;
289 		dst_efi_fmt->efi_id       = src_efi_fmt_32->efi_id;
290 		for (i = 0; i < dst_efi_fmt->efi_nextents; i++) {
291 			dst_efi_fmt->efi_extents[i].ext_start =
292 				src_efi_fmt_32->efi_extents[i].ext_start;
293 			dst_efi_fmt->efi_extents[i].ext_len =
294 				src_efi_fmt_32->efi_extents[i].ext_len;
295 		}
296 		return 0;
297 	} else if (buf->i_len == len64) {
298 		xfs_efi_log_format_64_t *src_efi_fmt_64 = buf->i_addr;
299 
300 		dst_efi_fmt->efi_type     = src_efi_fmt_64->efi_type;
301 		dst_efi_fmt->efi_size     = src_efi_fmt_64->efi_size;
302 		dst_efi_fmt->efi_nextents = src_efi_fmt_64->efi_nextents;
303 		dst_efi_fmt->efi_id       = src_efi_fmt_64->efi_id;
304 		for (i = 0; i < dst_efi_fmt->efi_nextents; i++) {
305 			dst_efi_fmt->efi_extents[i].ext_start =
306 				src_efi_fmt_64->efi_extents[i].ext_start;
307 			dst_efi_fmt->efi_extents[i].ext_len =
308 				src_efi_fmt_64->efi_extents[i].ext_len;
309 		}
310 		return 0;
311 	}
312 	return EFSCORRUPTED;
313 }
314 
315 /*
316  * This is called by the efd item code below to release references to the given
317  * efi item.  Each efd calls this with the number of extents that it has
318  * logged, and when the sum of these reaches the total number of extents logged
319  * by this efi item we can free the efi item.
320  */
321 void
322 xfs_efi_release(xfs_efi_log_item_t	*efip,
323 		uint			nextents)
324 {
325 	ASSERT(atomic_read(&efip->efi_next_extent) >= nextents);
326 	if (atomic_sub_and_test(nextents, &efip->efi_next_extent))
327 		__xfs_efi_release(efip);
328 }
329 
330 static inline struct xfs_efd_log_item *EFD_ITEM(struct xfs_log_item *lip)
331 {
332 	return container_of(lip, struct xfs_efd_log_item, efd_item);
333 }
334 
335 STATIC void
336 xfs_efd_item_free(struct xfs_efd_log_item *efdp)
337 {
338 	if (efdp->efd_format.efd_nextents > XFS_EFD_MAX_FAST_EXTENTS)
339 		kmem_free(efdp);
340 	else
341 		kmem_zone_free(xfs_efd_zone, efdp);
342 }
343 
344 /*
345  * This returns the number of iovecs needed to log the given efd item.
346  * We only need 1 iovec for an efd item.  It just logs the efd_log_format
347  * structure.
348  */
349 STATIC uint
350 xfs_efd_item_size(
351 	struct xfs_log_item	*lip)
352 {
353 	return 1;
354 }
355 
356 /*
357  * This is called to fill in the vector of log iovecs for the
358  * given efd log item. We use only 1 iovec, and we point that
359  * at the efd_log_format structure embedded in the efd item.
360  * It is at this point that we assert that all of the extent
361  * slots in the efd item have been filled.
362  */
363 STATIC void
364 xfs_efd_item_format(
365 	struct xfs_log_item	*lip,
366 	struct xfs_log_iovec	*log_vector)
367 {
368 	struct xfs_efd_log_item	*efdp = EFD_ITEM(lip);
369 	uint			size;
370 
371 	ASSERT(efdp->efd_next_extent == efdp->efd_format.efd_nextents);
372 
373 	efdp->efd_format.efd_type = XFS_LI_EFD;
374 
375 	size = sizeof(xfs_efd_log_format_t);
376 	size += (efdp->efd_format.efd_nextents - 1) * sizeof(xfs_extent_t);
377 	efdp->efd_format.efd_size = 1;
378 
379 	log_vector->i_addr = &efdp->efd_format;
380 	log_vector->i_len = size;
381 	log_vector->i_type = XLOG_REG_TYPE_EFD_FORMAT;
382 	ASSERT(size >= sizeof(xfs_efd_log_format_t));
383 }
384 
385 /*
386  * Pinning has no meaning for an efd item, so just return.
387  */
388 STATIC void
389 xfs_efd_item_pin(
390 	struct xfs_log_item	*lip)
391 {
392 }
393 
394 /*
395  * Since pinning has no meaning for an efd item, unpinning does
396  * not either.
397  */
398 STATIC void
399 xfs_efd_item_unpin(
400 	struct xfs_log_item	*lip,
401 	int			remove)
402 {
403 }
404 
405 /*
406  * Efd items have no locking, so just return success.
407  */
408 STATIC uint
409 xfs_efd_item_trylock(
410 	struct xfs_log_item	*lip)
411 {
412 	return XFS_ITEM_LOCKED;
413 }
414 
415 /*
416  * Efd items have no locking or pushing, so return failure
417  * so that the caller doesn't bother with us.
418  */
419 STATIC void
420 xfs_efd_item_unlock(
421 	struct xfs_log_item	*lip)
422 {
423 	if (lip->li_flags & XFS_LI_ABORTED)
424 		xfs_efd_item_free(EFD_ITEM(lip));
425 }
426 
427 /*
428  * When the efd item is committed to disk, all we need to do
429  * is delete our reference to our partner efi item and then
430  * free ourselves.  Since we're freeing ourselves we must
431  * return -1 to keep the transaction code from further referencing
432  * this item.
433  */
434 STATIC xfs_lsn_t
435 xfs_efd_item_committed(
436 	struct xfs_log_item	*lip,
437 	xfs_lsn_t		lsn)
438 {
439 	struct xfs_efd_log_item	*efdp = EFD_ITEM(lip);
440 
441 	/*
442 	 * If we got a log I/O error, it's always the case that the LR with the
443 	 * EFI got unpinned and freed before the EFD got aborted.
444 	 */
445 	if (!(lip->li_flags & XFS_LI_ABORTED))
446 		xfs_efi_release(efdp->efd_efip, efdp->efd_format.efd_nextents);
447 
448 	xfs_efd_item_free(efdp);
449 	return (xfs_lsn_t)-1;
450 }
451 
452 /*
453  * There isn't much you can do to push on an efd item.  It is simply
454  * stuck waiting for the log to be flushed to disk.
455  */
456 STATIC void
457 xfs_efd_item_push(
458 	struct xfs_log_item	*lip)
459 {
460 }
461 
462 /*
463  * The EFD dependency tracking op doesn't do squat.  It can't because
464  * it doesn't know where the free extent is coming from.  The dependency
465  * tracking has to be handled by the "enclosing" metadata object.  For
466  * example, for inodes, the inode is locked throughout the extent freeing
467  * so the dependency should be recorded there.
468  */
469 STATIC void
470 xfs_efd_item_committing(
471 	struct xfs_log_item	*lip,
472 	xfs_lsn_t		lsn)
473 {
474 }
475 
476 /*
477  * This is the ops vector shared by all efd log items.
478  */
479 static struct xfs_item_ops xfs_efd_item_ops = {
480 	.iop_size	= xfs_efd_item_size,
481 	.iop_format	= xfs_efd_item_format,
482 	.iop_pin	= xfs_efd_item_pin,
483 	.iop_unpin	= xfs_efd_item_unpin,
484 	.iop_trylock	= xfs_efd_item_trylock,
485 	.iop_unlock	= xfs_efd_item_unlock,
486 	.iop_committed	= xfs_efd_item_committed,
487 	.iop_push	= xfs_efd_item_push,
488 	.iop_committing = xfs_efd_item_committing
489 };
490 
491 /*
492  * Allocate and initialize an efd item with the given number of extents.
493  */
494 struct xfs_efd_log_item *
495 xfs_efd_init(
496 	struct xfs_mount	*mp,
497 	struct xfs_efi_log_item	*efip,
498 	uint			nextents)
499 
500 {
501 	struct xfs_efd_log_item	*efdp;
502 	uint			size;
503 
504 	ASSERT(nextents > 0);
505 	if (nextents > XFS_EFD_MAX_FAST_EXTENTS) {
506 		size = (uint)(sizeof(xfs_efd_log_item_t) +
507 			((nextents - 1) * sizeof(xfs_extent_t)));
508 		efdp = kmem_zalloc(size, KM_SLEEP);
509 	} else {
510 		efdp = kmem_zone_zalloc(xfs_efd_zone, KM_SLEEP);
511 	}
512 
513 	xfs_log_item_init(mp, &efdp->efd_item, XFS_LI_EFD, &xfs_efd_item_ops);
514 	efdp->efd_efip = efip;
515 	efdp->efd_format.efd_nextents = nextents;
516 	efdp->efd_format.efd_efi_id = efip->efi_format.efi_id;
517 
518 	return efdp;
519 }
520